package org.bouncycastle.asn1.x509;

import java.util.Enumeration;
import java.util.Vector;

import org.bouncycastle.asn1.ASN1Encodable;
import org.bouncycastle.asn1.ASN1EncodableVector;
import org.bouncycastle.asn1.ASN1OctetString;
import org.bouncycastle.asn1.ASN1Sequence;
import org.bouncycastle.asn1.ASN1TaggedObject;
import org.bouncycastle.asn1.DERObject;
import org.bouncycastle.asn1.DERObjectIdentifier;
import org.bouncycastle.asn1.DEROctetString;
import org.bouncycastle.asn1.DERSequence;
import org.bouncycastle.asn1.DERTaggedObject;
import org.bouncycastle.asn1.DERUTF8String;

/**
 * Implementation of <code>IetfAttrSyntax</code> as specified by RFC3281.
 */
public class IetfAttrSyntax extends ASN1Encodable {
    public static final int VALUE_OCTETS = 1;
    public static final int VALUE_OID = 2;
    public static final int VALUE_UTF8 = 3;
    GeneralNames policyAuthority = null;
    Vector values = new Vector();
    int valueChoice = -1;

    /**
     *  
     */
    public IetfAttrSyntax(ASN1Sequence seq) {
        int i = 0;

        if (seq.getObjectAt(0) instanceof ASN1TaggedObject) {
            policyAuthority = GeneralNames.getInstance(((ASN1TaggedObject) seq.getObjectAt(0)), false);
            i++;
        } else if (seq.size() == 2) { // VOMS fix
            policyAuthority = GeneralNames.getInstance(seq.getObjectAt(0));
            i++;
        }

        if (!(seq.getObjectAt(i) instanceof ASN1Sequence)) {
            throw new IllegalArgumentException("Non-IetfAttrSyntax encoding");
        }

        seq = (ASN1Sequence) seq.getObjectAt(i);

        for (Enumeration e = seq.getObjects(); e.hasMoreElements();) {
            DERObject obj = (DERObject) e.nextElement();
            int type;

            if (obj instanceof DERObjectIdentifier) {
                type = VALUE_OID;
            } else if (obj instanceof DERUTF8String) {
                type = VALUE_UTF8;
            } else if (obj instanceof DEROctetString) {
                type = VALUE_OCTETS;
            } else {
                throw new IllegalArgumentException("Bad value type encoding IetfAttrSyntax");
            }

            if (valueChoice < 0) {
                valueChoice = type;
            }

            if (type != valueChoice) {
                throw new IllegalArgumentException("Mix of value types in IetfAttrSyntax");
            }

            values.addElement(obj);
        }
    }

    public GeneralNames getPolicyAuthority() {
        return policyAuthority;
    }

    public int getValueType() {
        return valueChoice;
    }

    public Object[] getValues() {
        if (this.getValueType() == VALUE_OCTETS) {
            ASN1OctetString[] tmp = new ASN1OctetString[values.size()];

            for (int i = 0; i != tmp.length; i++) {
                tmp[i] = (ASN1OctetString) values.elementAt(i);
            }

            return tmp;
        } else if (this.getValueType() == VALUE_OID) {
            DERObjectIdentifier[] tmp = new DERObjectIdentifier[values.size()];

            for (int i = 0; i != tmp.length; i++) {
                tmp[i] = (DERObjectIdentifier) values.elementAt(i);
            }

            return tmp;
        } else {
            DERUTF8String[] tmp = new DERUTF8String[values.size()];

            for (int i = 0; i != tmp.length; i++) {
                tmp[i] = (DERUTF8String) values.elementAt(i);
            }

            return tmp;
        }
    }

    /**
     * 
     * <pre>
     * 
     *  IetfAttrSyntax ::= SEQUENCE {
     *    policyAuthority [0] GeneralNames OPTIONAL,
     *    values SEQUENCE OF CHOICE {
     *      octets OCTET STRING,
     *      oid OBJECT IDENTIFIER,
     *      string UTF8String
     *    }
     *  }
     * 
     * </pre>
     */
    public DERObject toASN1Object() {
        ASN1EncodableVector v = new ASN1EncodableVector();

        if (policyAuthority != null) {
            v.add(new DERTaggedObject(0, policyAuthority));
        }

        ASN1EncodableVector v2 = new ASN1EncodableVector();

        for (Enumeration i = values.elements(); i.hasMoreElements();) {
            v2.add((ASN1Encodable) i.nextElement());
        }

        v.add(new DERSequence(v2));

        return new DERSequence(v);
    }
}
